1. Oesophagus : Treatment of conditions such as oesophageal cancer, achalasia, and gastroesophageal reflux disease (GERD) that may require surgical interventions like esophagectomy or fundoplication.

2. Stomach : Management of gastric cancers, peptic ulcers, and other stomach disorders through procedures such as gastrectomy or minimally invasive surgeries.

3. Pancreas : Surgical treatment of pancreatic cancer, pancreatitis, and pancreatic cysts, often involving complex procedures like the Whipple procedure (pancreaticoduodenectomy).

4. Liver : Addressing liver diseases, including liver cancer, cirrhosis, and liver cysts, through surgeries like liver resection or liver transplantation.

5. Gallbladder and Bile Ducts : Treatment of gallstones, cholecystitis, and bile duct cancers through cholecystectomy and bile duct resection.

6. Intestines : Surgical management of colorectal cancer, Crohn’s disease, ulcerative colitis, and diverticulitis, involving procedures like colectomy or bowel resection.